Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations provided, the description carries the full burden of behavioral disclosure. It discloses three important behaviors: the secret is shown only once, replay returns the same key ID with a null secret, and revocation is needed before replacement. This is meaningful behavioral context beyond the schema.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three sentences, each carrying distinct information: the activation prerequisite, the idempotency/retry behavior, and the secret-display/revocation behavior. No filler or repetition of the schema.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a two-parameter creation tool with no output schema, the description covers the key operational concerns: activation, idempotent retries, one-time secret display, and revocation. The main gap is the meaning of 'scopes' and what values are valid, but the description is otherwise complete enough for an agent to call the tool correctly.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 0%, so the description must compensate for the two parameters. It mentions idempotencyKey and its retry semantics, but it does not explain what 'scopes' should contain or how they constrain the credential. The description adds some value for idempotencyKey but leaves scopes semantically under-specified.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a specific verb ('Create') and resource ('scoped credential'), and adds the qualifier 'after explicit activation,' which distinguishes it from a generic create operation. It doesn't explicitly name a sibling alternative, but the scoped-credential framing is clear enough to separate it from revoke_credential and list_credentials.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives clear operational guidance: create only after explicit activation, reuse idempotencyKey on retries, and revoke a lost credential before replacing it. It doesn't explicitly say when not to use this tool versus alternatives, but the activation prerequisite and revocation-before-replacement rule provide practical usage context.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.